d
$\frac{6}{1000}(G+4990)=30 $
$\Rightarrow G+4990=\frac{30,000}{6}=5000 $
$\Rightarrow G=10 $
$\frac{6}{1000} \times 10=\left(1.5-\frac{6}{1000}\right) S $
$\Rightarrow S =\frac{60}{1494}=\frac{2 n}{249} $
$\Rightarrow=\frac{249 \times 30}{1494}=\frac{2490}{498}=5$